Effects of aerobic exercise on the regulation of mitochondrial carrier homolog-2 and its influence on the catabolic and anabolic activity of lipids in the mesenteric adipose tissue of obese mice

The aim was to understand the direct impact of aerobic short-term exercise on lipid metabolism, specifically in regulating the mitochondrial carrier homolog 2 (MTCH2) and how it interferes with lipid metabolism in mesenteric adipose tissue. Swiss mice were divided into three groups: control, sedentary obese, and exercised obese. The obese groups were induced into obesity for fourteen weeks of a high-fat diet, and the trained submitted to seven aerobic exercise sessions. The exercise proved the significant increase of the pPerilipin-1, a hormone-sensitive lipase gene, and modulates lipid metabolism by increasing the expression of Mtch2 and acetyl Co-A carboxylase, perhaps occurring as feedback to regulate lipid metabolism in adipose tissue. In conclusion, we demonstrate, for the first time, how aerobic physical exercise increases Mtch2 transcription in mesenteric adipose tissue. This increase was due to changes in energy demand caused by exercise, confirmed by observing the significant reduction in mesenteric adipose tissue mass in the exercised group. Also, we showed that physical exercise increased the phosphorylative capacity of PLIN1, a protein responsible for the degradation of fatty acids in the lipid droplet, providing acyl and glycerol for cellular metabolism. Although our findings demonstrate evidence of MTCH2 as a protein that regulates lipid homeostasis, scant knowledge exists concerning the signaling of the MTCH2 pathway in regulatingfatty acid metabolism. Therefore, unveiling the means of molecular signaling of MTCH2 demonstrates excellent potential for treating obesity.

Short-term strength exercise reduces the macrophage M1/M2 ratio in white adipose tissue of obese animals

Obesity can exacerbate the systemic inflammatory process, leading to increased infiltration of monocytes in white adipose tissue (WAT) and polarization of these cells into pro-inflammatory M1 macrophages, while reducing the population of anti-inflammatory M2 macrophages. Aerobic exercise has been shown to be effective in reducing the pro-inflammatory profile. However, the impact of strength training and the duration of training on macrophage polarization in the WAT of obese individuals have not been widely studied. Therefore, our aim was to investigate the effects of resistance exercise on macrophage infiltration and polarization in the epididymal and subcutaneous adipose tissue of obese mice. We compared the following groups: Control (CT), Obese (OB), Obese 7-day strength training (STO7d), and Obese 15-day strength training (STO15d). Macrophage populations were evaluated by flow cytometry: total macrophages (F4/80+), M1 (CD11c), and M2 (CD206) macrophages. Our results demonstrated that both training protocols improved peripheral insulin sensitivity by increasing AKT phosphorylation (Ser473). Specifically, the 7-day training regimen reduced total macrophage infiltration and M2 macrophage levels without altering M1 levels. In the STO15d group, significant differences were observed in total macrophage levels, M1 macrophages, and the M1/M2 ratio compared to the OB group. In the epididymal tissue, a reduction in the M1/M2 ratio was observed in the STO7d group. Overall, our data demonstrate that 15 days of strength exercise can reduce the M1/M2 ratio of macrophages in white adipose tissue.